1. Field of the Invention
This invention relates to a liquid composition for recording on a recording material such as paper, resin film, etc. according to an ink-jet system or by a writing instrument such as a fountainpen, a felt pen, etc., generally called "ink", (the liquid composition will be hereinafter referred to as "ink"), and to a method for recording with the ink.
2. Description of the Prior Art
The ink jet recording system comprises forming ink droplets according to any of various ink injection systems (e.g. an electrostatic suction system, a system of giving mechanical vibrations or displacements to an ink by a piezoelectric device, a system of heating an ink and utilizing the pressure developed thereby, etc. are known), and then depositing a portion or all of the ink droplets onto a recording material such as paper, etc., thereby making recording. In the case of using a writing instrument such as a fountainpen, a felt pen, a ballpoint pen, etc., the recording is made by discharging an ink through capillaries and allowing the recording material to accept the discharged ink as is well known. The known ink for use in the ink jet recording system or for the writing instrument includes solutions or dispersions of various water-soluble dyes or pigments in water or a liquid medium comprising water and a water-soluble organic solvent.
It is needless to say that various properties are required for the conventional ink as described above, and the most important property is, among others, such a liquid stability that neither clogging nor precipitation takes place in a nozzle or orifice or at a pen edge of recording apparatus during the recording with the ink, or during interruptions of recording, or during a prolonged intermission. In the ink jet system, particularly an ink jet system based on a thermal energy, the liquid stability is particularly important, because foreign matters are liable to deposit on the surface of a thermal head due to changes in temperature. In the case of the conventional ink, several additives are required to satisfy various conditions such as ink discharge conditions, a long term storage stability, distinctness and density of an image during the recording, surface tension, electrical properties, etc., or various impurities are inevitably contained in the dyes. Thus, there are various problems such as clogging in the nozzle or orifice of an ink jet device, deposition on the surface of a thermal head, precipitation during the long term storage etc., which are reasons for delayed spread of the ink jet recording system in spite of its various distinguished characteristics.